Electron tube



, Nov. 2,1937.

ELECTRON TUBE Original Filed sept. 15. 1926 70 POSITIVE V01 H65 300/76! ram/m 7 70171465 50am-- I I IIIIIIMMTIZ M/Pl/T mu l-11mmnewm-l l m l l 'l m l l INVENTO R s KENNETH W. JARVIS V R ssu. M. LAIR ATTORNEY u K. w. JARVIS n AL Re. 20,545 r Reamer Nov. 2, 1931 UNITED STATES PATENT OFFICE Original No. 1,903,569, date Our invention relate and more particularly a ELECTRON TUBE Kenneth W. Jarvis,

RussellM. Bl

No. 135,604, September for reissu rrangement's 'oi tube structure for securing increased operating efliciency over that heretofore 0 One of the objects of our invention is to proe a construction 01' elect vid btainable.

ron discharge device where substantially all electrostatic coupling between output and in Another object of a. construction of elec in the phenomena 0 our 1 put electrodes is eliminated.

nvention is to provide tron discharge device wheref secondary emission is employed for securing substantially pure relay action for increasing the charge device to in Another object nction of our i one way repeater that it does not absorb input or output circuits.

Another object oi our '1 an electron tube construc ability of the electron disas a repeater. nvention is to provide and also has the advantage in power from either the nvention is to provide tion and arrangement of the electrodes therein for the securing 0! high amplification in signal the principle 01' seconds. in the output circuit is from the princ relied upon for tube system.

Other and further obj reside in the structural re ,ity of electrodesand elect multiple electron tube an cl after by reference in which Figure 1 is a diagrammati the several electrodes electron discharge devi is a diagrammatic circuit ing the principle'oi' operati structure oi our inventi ing the principles of o trates a modified circuit electron tube of our in shown by Fig. 3.

receiving systems where vention; trates a slight modification of emission current 8.10118 employed as diflerentiated iple where the functioning of the electron primary emission is ects of our invention lationship 01' a pluralrostatic shields within fully described hereinto the accompanying drawing c representation of employed in one type of cc of our invention; Fig; 2

arrangement illustraton of the electron tube on; Fig. 3 illustrates a discharge device employur invention; Fig. 4 illusarrangement for the and Fig. 5 illusthe arrangement Heretoiore in the communication art, sensltive electron tube am employed in signal been been considerably limited pliflcation circuits have been 7 receiving circuits, but it has found that their operating emciency has and impaired by the 0 April 8, 1.935, Serial No. 36 Claims. (Cl. 179 -171l' s broadly to electron tubes existence New Rochelle, N. Y., and air. Teaneck, N. I.

d April 11, 1933., Serial Application 18,108

of capacity coupling between the output and control electrodes of each of the tubes. Various methods have been proposed for compensating such methods are merely systems tion which do not olfer a cure for coupling. constructi for the undesired capacity coupling, but

of compensathe inherent By our invention we provide a novel on of the electron discharge device so as to substantially eliminate all output to input capacity cou between t Among we employ in the o arge device of our invention the phenomena pling which previously occurred he tube electrodes. 1

other novel features in combination,

peration of the electron disol secondary emission. A'primary source of electrons, such as a heated cathode, is provided within an eva cuated vessel, the electronic movement therefrom being controlled by a grid electrode. This controlled electron stream impinges against a treated respect to the cathode.

anode held at a positive potential with We have termed this anode the collector plate and while it is held at a. positive potential with respect to the oathode, .it is substantially grounded to the cathode so far as alternating currentsare concerned.

' This collector plate serves as a source of secondary emission for the fourth element, the as to receive the secondary emission of the collector pla output plate circuit. A' "output plate, is placed so The positions of the cathode, control grid, collector .plate and output plate are so chosen that shiel ode, with control gr er design ding elements, grounded to the cathrespect to alternating currents, may

: be placed between the output plate and the id. These shielding elements by propmay at the same time be placed between the output plate and the cathode. The purpose of these shielding elements is twofold. First, to sub trostatic coupling b control grid, and se the outpu primary e vent any plate directly. tion of these s that it is tween any c plate witho ments. the shield to prevent stantially prevent any elec,- etween the output plate and cond to substantially prevent t plate potential from influencing the mission from the cathode, and to preprimary emission reaching the output To this end, the shape and posihielding elements should be such impossible to draw a straight line behosen points on the grid and output e shielding elements, hereafter termed may at the same time be placed so as any straight line being drawn from the ate to the cathode without passing he shield, This construction substanut passing through the shielding eletially frees the tube from any inherent undesired electrostatic coupling.

The novel relay action due to the phenomena of secondary emission is obtained by the arrangement of the electrodes within the tube. In the, usual three element electron tube heretofore available in the art, the voltage across the output load adds and subtracts from the applied direct plate voltage and materially aiifectsthe amplifying characteristics. In aregenerative radio receiver it often causes the establishment of a periodic variation in current which becomes evident in the form of undesired noises. In an amplifier it may cause distortion. In an oscillator it causes a change in oscillating frequency as the output load is changed. These disadvantages are avoided in the tube of positive potential of the output plate is made high enough with respect to the collector plate, all of the secondary electrons from the collector plate will travel to the output plate. This positive potential necessarily is the equivalent of the plate saturation potential of a two element tube. If the secondary emission is small, a small potential difference may be sufficient. For higher values of secondary emission a correspondingly higher voltage might be necessary. It will be understood, however, that if this maintained potential difference between the output plate and collector plate, minus the maximum output potential across the load, is still greater than the plate saturation potential as defined above, changing the output load voltage will have substantially no effect on the characteristics oi. the tube and the system will be free from all such detrimental effects as noted above.

To an additional external voltage in the output plate circuit, (saturation potential being maintained) the tube offers an infinite impedance. Therefore the tube will absorb no power'from the external system, and when applied to anelectrical network will not cause any loss to that network system. As typical of the beneficial results obtained in our system, the selectivity and amplification in a radio frequency amplifier are correspondingly improved.

The relay function of the electron tube structure of our invention, due to'the phenomena of secondary emission, is such that the amplifying ratio may be made very large. By the proper preparation of the collector plate the secondary emission may be made a large multiple of the primary emission and the amplifying characteristics of the tubecorrespondingly increased. BY- utilizing a multiple number of electrodes within the tube structure amplification at extremely high ratios is obtainable.

Referring to the drawing in more detail, we

have represented at Fig. 1 the electron tube structure of our invention employing a filament or cathode designated by reference character I surrounded by a control grid 2. The collector plate is represented at 3 connected to a point of positive potential 39 on battery I2 as represented in Fig. 2. The output plate 4 is represented as separated from the control grid 2 and cathode I by means of the shield 5 for reducin undesired electrostatic coupling and preventing the flow of primary emission to the output plate 4. The output electrode 4 and the electrode 5 f each have alternately arranged solid and open portions, and the solid portions of the shield electrode are in alignment with the electron emitter and the solid portions-of the output electrode.

In Fig. 2 we have shown a diagrammatic cirby the tuning condenser I5. It will be understood our construction. When the,

also function as a of relay stages as illustrated in Fig. 3.

. I5 across battery I2.

. ode for the next cult arrangement such as might be used in a radiofrequency amplifier system wherein the input potential is supplied through a transformer system having primary winding 1 with a 'secondary winding 8 coupled thereto and tuned by means of a. condenser 9. The cathode I is heated from a suitable source ID, the cathode being grounded at II as is also the electrostatic shield 5, which connects to one side of the cathode. The output circuit of such a radio frequency amplifier system is represented as including the primary winding ll of coupling transformer 32 connected between the output plate 4 and high potential battery i2. Secondary winding II is coupled to primary winding 4i and is shunted that while the tube structure is so devised as to make it a more efficient amplifier, the tube may detector, an oscillator, or modulator, or in other ways well known to the art.

In order to increase the amplification obtainable in the electron tube device of our invention a multiple tube may be arranged as represented in Fig. 3 for obtaining a lower effective coupling capacity between the grid electrode 2 and the output plate I1, thereby improving the characteristics of the tube system. While the capacity coupling existingin the. tube circuit represented in Fig. 2 is substantially negligible, this capacity coupling is further reduced by using a number In addition to serving as a' better amplifier an electron tube constructed in the general manner of Fig. 3 mayserve in other ways, such as a detector or oscillator or modulator.

In Fig. 3 of the drawing reierencecharacter i represents the cathode serving as a source of electrons which are directed to an intermediate collector plate l5 by. virtue of the positive charge imparted to collector plate I5 from a potential source such as the tap 40 on the potentiometer The grid electrode 2 serves to control the primary emission of cathode I with respect to the intermediate collector plate IE, but thereafter the'intermediate collector plate I6, which is properly treated to produce secondary emission, serves as a cathode'for the intermediate output plate I! connected to a point of higher positive potential 23 on potentiometer I5. The output intermediate plate I! is treated to produce secondary emission and serves as a cathsucceeding plate element l3, connects to point 43 on potentiometer l5 at the next higher positive potential. The plate I element I3 serves as a cathode for plate I9 which connects to the positive point 30 along potentiometer I5. In a similar manner plate members 20,22, 24 and 25 are arranged to receive and emit electrons to the succeeding plates 2I, 23, 25 and 21 with an electrostatic shield 5 interposed between the successive plate electrodes. The plate member 21 finally emits electrons which bombard the output plate I con nected to the output circuit. It will be observed that plate members 2|), 2|, 22, 23, 23, 25, 26 and 21 connected to points 44, 3|, 45, 32, 4B, 33, 41 and 34 along potentiometer i5, which are maintained at successively higher potentials. Con-p densers 35, 36, 31, 38, 49, 50, 5|, 52, 53, 5G, 51, 53 and 53' maybe connected between the suc- 7 cessive plate electrodes for avoiding undue resistance coupling, due to the method of applying the positive potential to the intermediate collector plates.

The undulatory or zig-zag path of the elec- 7 which tron stream from the source to the output elecadjacent said electron emitting body, a pair of trode is indicated by the arrows oi Fig. 3. This plate electrodes adapted to'be charged to diiferent tentials obviously result in an electric field which, tially eliminating the eil'ects of capacity coupling with respect to electron-emitting surfaces, has a between said grid electrode and-the plate elec- 10 component normal to the'respective surfaces and trode of largest positive potential;

directed path or branch lying at a substantial said plate electrodes being mounted adjacent said 20 trated in Fig. 3, the group f aces at ea h posed between said electron emitting" body and side of the axis of the tube each constitute an the plate electrode immediately adjacent said as m y r el tr de means of lon i ud n y control member for eliminating the elrects of alined surfaces. the active portions of each .surcapacity coupling, g 25 face or each electrode means being iongitudi- 3, An electron tube om ri in a eva uated naliy spa ed with respect to an opposed pair of vessel containing an electron emitting b0 active portions of the other electrode means. control eiectrodegan output plate electrode and All of the electrodes may be mounted within a plurality of collector plates, means interposed the same envelope 8.- The control electrode may between the first of said collector plates and both tions between the electrodes of any two 01 more 4, An electron tube comprising an evacimted Pa f l trodes- The multiplying action of vessel, an electron emitting body in said vessel, a

substantially self-sustaining source of electrons. tel-posed b tw d t l electrode and a such as radioactive material. The plate elements output t and means Intel-posed b t sum 6, 7, 8, 3, 20, 25 d 37110 ceeding, collector plates for eiectrostaticaliy secondary emission .under conditions 01' bom- 5. An electron discharge device, comprising an dment. evacuated vessel, a cathode to primary eiec- The output of the tube system may be o pl rons, a pin all y of electrodes, a collector plate t e succeedin Circuit by a s 0 the radio elec rode mou t emi secondary electrons frequency choke coil 54 and condenser 55 to the under b b t of pflmaryelectrons, an tuned output circuit |4I5. output plate electrode positioned with respect to 59 e p incipl s or our n en i n ma e emsaid collector plate to receive the secondary elecbodied in a variety of different const u tron emission from said collector plate electrode,

Of positive potential and the eiectrostatic shields elec ron control member, applets electrode 80 parts of Fig. 3. I Other changes or improvements 5 05 may be made, as will readily suggest themselves posedbetween said output plate and said conto those skilled in the art and we intend no trol member in such manner that a --straight limitations other than are imposed by the scope line cannOt. b drawn through any point on the of the app n claims output plate and said control member without at we claim as new and desire to secure passing through said shielding element. by Letters Patent 01 the United States is as 7. An electron tube comprising an evacuated 7 follows:

electron emitting body, a grid electrode mounted cathode and. each with respect to the preceding 75 collector plate interposed between the output interposed between any d collector plates'and an electrostatic shield interposed be- 5 tween said control electrode and said output plate and connected to said cathode for eliminating output to input capacity coupling between said electrodes.

8. An electron tube comprising vessel, an electron emitter "disposed therein, a control electrode adjacent thereto, a collector plate, an output plate adjacent said collector plate, said output plate having a plurality of alternate, solid and open portions, and a shield having a plurality or solid portions disposed adja- 9. An electron tube comprising an evacuated oi electrons therein, a

, pair of concentrically positioned plate electrodes ut said primary source of electrons at I therefrom, the outermost plate electrode constituting a collector plate the electrons emitted by the primary source or electrons, the innermostplate electrode constituting an output plate and having a multiplicity of alternate, solid and open portions, a control electrode disposed about said primary source of electrons, and a shield constituted by a plurality of alternate, solid and open portions with the solid portions ther aligned with sai d priof electrons while said output plate discharge from said collector plate.

source trcde constituting an secondary bombardment with respect to said collector plate, said output plate having a plurality of alternate,

being in l to f the solid por ons o said output plate for preventi g primary emission fro sai pr ouroe of electrons from 11. An electron tube vessel, a primary sourc control electrode dispo d adjacent plurality of plate electrodes disposed at different cc of elec trons, the o termost plate electrode constituting collector plate, e innermost plat electro e constituting an a shield having a plurality of substantially semicircular s lid portions separated by open porplate and the cathode, the control electrode being i soan evacuated tions, the solid portions thereof being disposed in alignment with the solid portions or said output plate and the open portions disposed in alignmen sa doutput plate whereby p said primary source of electrons is from reaching said output plate while bombarding said collector'plate.

12. An electron tube device comprising an evacuated vessel, a filament electrode, a control electrode, a pair of plate electrodes adapted to be ositive potentials, one of an electron emitting body, and with said filament electrode and interposed b tween said output plate and said filament electrode'for eliminating the effect of electrostatic capacity between said control electrode and said output plate.

13. In an electronic device, the combination of an electron source, a plurality of staggered elecdisposed at successively greater distances h'capable of emitting under electron impact secondary electrons, sai electrodes being adapted to have applied thereto voltages positive with respect to the source and of progressively increasing values in conformity to the remo nessof 5 ing from the source so that thin the tube aggercd elect ode to follow separate paths, and

for collecting the leaving the staggered electrode most remote from urce. An electron discharge amplifier comprising 14. a prima output anode and ting areas distributed in s mediate the primary electron emitter and the on put anod said areas and said output electrode nate areas I causi the pr uced electric f1 within the tube to e the lectron stream 0 impinge upo d i ve each of sai emitting n an areas along different paths having a velocity component in the directionoi the greatest positive voltage connection point.

15. The electron discharge amplifier claimed in the preceding claim comp sing, n addition, means to control the pri electron emission reaching the first of said im act electron emitreas. The device claimed in claim 14 comprising,

16 in addition, means ispose intermediate the prieleotron emitter and the output anode to control the intensity or the electron stream reaching the e member.

'I. I combination, for producing a controlled electron strea p ahty or oppose surfaces aria a y secelectron stream,

. ating electrons by V by secondary emission, the first electron emission from the second that the electrons leaving each surface successively reach the next succeeding surface, and an output electrode for collecting the electron emission from the last of said plurality of pairs of surfaces.

18. In an electron tube device, a source of electrons, a plurality of opposed and longitudinally arranged surfaces adapted to liberate electrons of said surfaces being positioned to receive electrons from said source, said surfaces being adapted when subjected to a potential gradient from one surface to the next to produce an undulating progression of electrons from one surface to the next 'succeeding surface, and an output electrode for collecting the electron emission from the last of said surfaces.

19. In combination, means for producing a grid-controlled electron stream, a pair of opposed surfaces adapted to liberate electrons by secondary emission, the first of said surfaces being positioned 1 to intercept said electron stream, means cooperating with said surfaces to direct electrons leaving said first surface to the second surface, and an output electrode for collecting the surfaces.

20. In an electron tube device, a source'of electrons, a plurality of opposed and longitudinally disposed surfaces having the property of liberating electrons by secondary emission and adapted to be maintained at successively higher potentials with respect to said source, the first of said surfaces being positioned to receive electrons from said source, means cooperating with said surfaces to restrict the travel of electrons leaving each surface except the last substantially to a path leading to the next succeeding surface, and

an output electrode for collecting the electron emission from the last of said surfaces.

21. In an electron tube device, a. source of electrons, an output electrode, and a plurality of pairs of opposed surfaces havingthe property of libersecondary emission, said opposed surfaces being progressively arranged along the electron path between said source and said electrode and charged at successively higher positive potentials in a direction from the source towards said electrode, thereby to establish between said source and said electrode an undulating electric field for directing electrons to a surface from the adjacent opposed surface positioned closer to the source.

22. In combination, a source of electrons, op-. posed surfaces adapted to liberate electrons by secondary emission, and means for producing between said opposed surfaces an electric field for establishing an undulatory progression of electrons between and longitudinally of said opposed surfaces, one surface including a portion .positioned to receive electrons from said source.

23. The invention as claimed in claim 22, in combination with an output electrode positioned .to interceptthe streamof secondary electrons liberated from one of said surfaces.

24. In an electron tube device, a source-of electrons, an output electrode, and aplurality of surfaces adapted to liberate electrons by secondary emission, a portion of one surface being positioned to'receive an electron stream from said source, another of said surfaces having a'portion opposed to said stream-intercepting portion and spaced longitudinally thereof in a direction towards said output electrode, said stream-intercepting portion of the first of said surfaces being adapted to be charged at a positive potential higher than that of said source and lower than that of the said opposed portion of the second of said surfaces. I

25. In an electron tube device, a source of elec-- trons, an output electrode, a pair of electrode means opposed to each other and including surface portions adapted to liberate electrons by secondary emission, the electron-liberating portions of each electrode means being longitudinally alined with respect to adjacent portions of the same electrode means and longitudinally displaced with respect to an opposed pair of adjacent electron-liberating portions of the other electrode means, and means for charging the respective electron-liberating portions at potentials increasing progressively in .a direction from said source to said output electrode.

26. In an electron tube device, a source of electrons, an output electrode, and a pair of electrode means opposed to each other and including surface portions adapted to liberate electrons by secondary emission, the electron-liberating portions of each electrode means being longitudinally 'alined with respect to adjacent portions of the same electrode means and longitudinally displaced with respect to an opposed pair of adjacent electron-liberating portions of the other electrodemeans, an electron-liberating portion of one electrode means being positioned to receive electrons from said source and said output electrode being positioned to intercept the electrons liberated by one of said electron-liberating portions, whereby an undulating progression of electrons takes place between said electrode means when respective electron-liberating portions are at progressively higher potentials as viewed in a direction from said source towards said output electrode.

27. In combination, a source of electrons, a plurality of electrode means having surfaces adapted to liberate electrons by secondary emission, means for producing an electrostatic field to constitute the agency for guiding electrons from one surface to another, said field-producing means including electrodes additional to said electrode means and a current source for establishing on said electrode means and said electrodes potentials-with respect to said source of electrons which create the guiding electrostatic field, a portion of one electron-liberating surface being positionedto receive electrons from said source, and

an electrode positioned to receive the electrons emitted from a portion of an eleotrondiberating surface that is spaced from said electron-receiving portion;

28. In combination, a source of electrons, a pair of electrode means having opposed. surfaces each adapted to liberate-electrons by secondary emission, the electron-liberating surfaces of each electrode means being adapted to have applied thereto voltages positive with respect to said source and of values progressively increasing with the remoteness of the surface from the source, a portion of an electron-liberating surface adjacent said source being positioned to receive electrons from said source, and an output electrode for receiving the electrons emitted from a portion of an electron-liberating surface furthest from said source.

trons positioned at the termination of electron-emitting positive with relation to said source of electrons,

a control electrode, electrode means between said source of electrons and certain of said secondaryelectron-emitting electrodes held at such potential with relation to the said certain secondary-electron-emitting -electrodes as to shield the electrons in the vicinity of said control electrode from the strong electro-positive field of said certain secondary-electron-emitting electrodes, and an output electrode more positively charged than any other electrode in the tube.

31. In combination, means to cause a flow of electrons, means for causing the developed electron now to follow a succession of reversing paths, and a surface adapted to emit secondary electrons in greater number than the impinging 6160- each independent reversing path.

32. The combination with an output electrode and electrostatic means for establishing a fiow of electrons along a zis-zas path terminating at said output electrode, of surfaces adapted to liberate secondary .electrons positioned at thejunctions of adjacent branches of said zig-zag path.

33. The combination of a pair of opposed surfaces adapted to liberate secondary electrons, an output electrode, and means for electrostatic field between said surfaces and said output electrode to direct to one of said surfaces the secondary electrons released from the other of said surfaces, said means including a source of direct current potential for maintaining said output electrode at a more either of said surfaces.

positive potential than 34. ,In an electron tube, the combination of an output electrode having an opening therethrough for the passage of an electron stream, a source of electrons and a surface for emitting secondary electrons positioned at opposite sides of said output electrode, means for difference between said electron source and said surface to create a flow of electrons from said source through said output electrode and to said surface, whereby secondary electrons are emitted from said surface, and means maintaining said output electrode at a higher direct current potential than said surface, whereby secondary 36. An electronic device comprising electrostatic means including impact surfaces for producing anelectron flow along a path having a plurality of serially disposed segments of successively different directions, said impact surfaces being adapted to emit secondary electrons in a number greater than the number of impinging electrons and being located at the junctions of adjacent segments 0f.said path, and an output electrode positioned to collect the electron fiow developed by travel of the electron stream along a succession of, the segments of said path.

mm W. Jmws. RUBSELL M. 3mm.

establishing a potential 

